Highly efficient 1,4-additions of electron-deficient aryl boronic acids with a novel rhodium(I) quinonoid catalyst

Rhodium(I) quinonoid catalysts are a remarkably efficient new class of reagents for the conjugate addition of aryl boronic acids. Herein, we describe the use of these reagents in catalyzing the highly efficient addition of a broad range of boronic acids, including heteroaromatic and the first example of trihalogenated aryl boronic acids.